A conventional packet forwarding process is entirely controlled by a switch/router. The switch/router controls an acquired packet by using a conventional forward table. Content of the conventional forward table is determined according to a format agreed by microcode of a forwarding plane, and a control plane. That is, content in each field of the conventional forward table is agreed by the microcode of the forwarding plane and a drive of the control plane. The conventional forward table may be a bridge table or a route table. A packet control process entirely implemented by control by the switch/router has advantages of high performance and mature technologies. However, the packet control process entirely implemented by control by the switch/router is insufficiently flexible, and cannot well adapt to a change of a service requirement.
With development of technologies, an openflow technology emerges. The openflow technology changes a forwarding process originally entirely controlled by a switch/router to a forwarding process jointly controlled by an OpenFlow switch and a controller. The OpenFlow technology implements separation between data forwarding and route control. The OpenFlow technology completes a forwarding processing process, from input to output, of a packet by using a pipeline of a multi-stage flow table. Specifically, the flow table is formed by multiple flow table entries, and each flow table entry corresponds to one forwarding rule. A destination port of the packet is obtained by searching the flow table. The flow table includes a match field, an instruction field, and a counter field. The match field is used to match a packet. The instruction field is used to process a packet. The processing may be modifying a packet, encapsulating a packet, decapsulating a packet, or forwarding a packet. A packet control process implemented by using the OpenFlow technology can flexibly adapt to a change of a service requirement. However, the OpenFlow technology has low performance and the technology is immature.